There are many web apps out there for real-time collaboration, but getting by free and good ones is not that easy. That is why I am sharing The 7 Coolest Real-time Collaboration Web Apps You Might Not Know About But Should. Read each entry in the list and see which tool suits your needs best.

crocodoc takes your PDFs, Word documents, and PowerPoint presentations, and lets you view and mark them up online. Documents can be shared with others, who can collaboratively highlight or strikeout text, add notes and comments, and make revisions.

notapipe.net is a web service that allows you to edit text files in a realtime collaborative environment, from everywhere. This means multiple users can edit the same document simultaneously and changes are near istantly dispatched to every connected user.

Creately is a visual collaboration platform used by project teams to communicate more effectively. With Creately’s easy to use interface and Shared Projects, everyone on your design, development and business teams can collaborate on software designs, wireframes, business & strategy diagrams easily.

tgethr is for Project teams who need a no-frills, secure email-based collaboration solution and useful for families, friends, and clubs who don;t need the overhead of more complicated solutions. This is also best for remotely located
people who still use email as a primary collaboration mechanism. With tgethr all correspondence over the web and email can be safely encrypted.

ShowDocument is an online collaboration platform that lets you conduct web meetings and document sharing and collaboration sessions with clients and colleagues, and brainstorm using interactive whiteboards.

I’ve used a couple of these but will have to explore the others. Personally, I switched from Creately to LucidChart – http://www.lucidchart.com – because I found the real-time collaboration much more effective and robust. It could actually handle a lot of people on the same diagram.

This is definitely an interesting collection of collaboration tools. If I may add, I would also suggest taking a look at Agilewords (http://bit.ly/d4VFkV). If you work with a team and extensively use word documents, Agilewords is a perfect match. This platform maintains the integrity of the document, so there are no formatting errors if the file is downloaded. Users can see comments from their team members, fostering a deeper sense of collaboration than what traditional document collaboration platforms offer. As opposed to Crocodoc, Agilewords does not force you to publish the document in a read-only format such as PDF and it also comes with notifications, scheduling, and review workflow